Christie Brinkley calls ex-husband Billy Joel 'OUR piano man' after brain diagnosis
Christie Brinkley is showing support for her ex-husband Billy Joel following news of his recent brain diagnosis.
The supermodel, who shares daughter Alexa Ray with the legendary singer, posted a video on Instagram Saturday -- just one day after Joel revealed he had been diagnosed with normal pressure hydrocephalus.
In the clip, Brinkley and her daughter, Sailor Brinkley Cook -- whom she shares with ex-husband Peter Cook -- are seen enjoying one of Joel's concerts and sharing laughs with the musician.
"Dear Billy, The whole Brinkley gang is sending you lots of love and good wishes for a full and speedy recovery," she wrote in the caption. "I was looking for some cute photos of you and Alexa to send you, when I came across this clip from a recent concert. It made me laugh ..but it also reminded me of all the joy you create, and all the sensational sing a longs you've lead."
"You turn an arena of strangers into a living room full of friends as we all sway in unison," she continued. "I'm sure I'm speaking for everyone in that room when I say please take good care of yourself, we all want you back in that white hot spotlight, you're OUR piano man.'
"And we're always in the mood for your melodies And we all hope you're feeling alright!" Brinkley concluded the heartfelt note. "We Love You, the kids, me and a whole bunch of full arenas!"

Joel and Brinkley were married from 1985 to 1994 and share one child, Alexa Ray. Both have two additional children from other relationships.
Joel shared his diagnosis on Friday in an Instagram post, where he also announced that his upcoming concerts have been canceled due to health concerns.
Normal pressure hydrocephalus is one of two types of hydrocephalus, an "abnormal buildup of cerebrospinal fluid deep within the brain," according to the U.S. National Institute of Neurological Disorders and Stroke.
CSF is the fluid that fills the brain's ventricles, or cavities, helping to cushion both the brain and spinal cord. When the flow of this fluid is disrupted and begins to accumulate in the ventricles, it can lead to normal pressure hydrocephalus.
This condition can happen at any age but is more common among older adults and can lead to problems with walking, bladder control, and cognitive functions like thinking and reasoning, according to the NINDS.
"Good Morning America" has reached out to Joel's rep for additional comment about his diagnosis.